Peroxisomes are ubiquitous organelles in eukaryotes that fulfill various important metabolic functions. In this study, we investigated the role of docking/translocation module (DTM) peroxins, mainly FvPex8, FvPex13, FvPex14, and FvPex33, in Fusarium verticillioides development, virulence, and fumonisin B₁ (FB₁) biosynthesis. Protein interaction experiments suggested that FvPex13 serves as the central DTM subunit in F. verticillioides. Notably, FvPex8 and FvPex14 did not show direct interaction in our experiments. We generated gene-deletion mutants (ΔFvpex8, ΔFvpex13, ΔFvpex14, ΔFvpex33, ΔFvpex33/14) and further examined the functional role of these peroxins. Deletion mutants exhibited disparity in carbon nutrient utilization and defect in cell-wall integrity when stress agents were applied. Under nutrient starvation, mutants also showed higher levels of lipid droplet accumulation. Particularly, ΔFvpex8 mutant showed significant FB₁ reduction and altered expression of key FB₁ biosynthesis genes. However, FvPex13 was primarily responsible for asexual conidia reproduction and virulence, while the ΔFvpex33/14 double mutant also showed a virulence defect. In summary, our study suggests that FvPex13 is the central component of DTM, with direct physical interaction with other DTM peroxins, and regulates peroxisome membrane biogenesis as well as PTS1- and PTS2-mediated transmembrane cargo transportation. Importantly, we also characterized FvPex8 as a key component in F. verticillioides DTM that affects peroxisome function and FB₁ biosynthesis.

Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

过氧化物酶体是真核生物中普遍存在的细胞器，可实现各种重要的代谢功能。在本研究中，我们研究了对接/易位模块 (DTM) 过氧化物酶（主要是 FvPex8、FvPex13、FvPex14 和 FvPex33）在轮枝镰孢发育、毒力和伏马菌素 B ₁ (FB ₁ ) 生物合成中的作用。蛋白质相互作用实验表明 FvPex13 作为轮枝杆菌中的中心 DTM 亚基. 值得注意的是，FvPex8 和 FvPex14 在我们的实验中没有表现出直接的相互作用。我们产生了基因缺失突变体（ΔFvpex8、ΔFvpex13、ΔFvpex14、ΔFvpex33、ΔFvpex33/14）并进一步检查了这些过氧化物的功能作用。当应用应激剂时，缺失突变体表现出碳营养利用差异和细胞壁完整性缺陷。在营养匮乏的情况下，突变体也表现出更高水平的脂滴积累。特别是，ΔFvpex8 突变体显示出显着的 FB ₁减少和关键 FB _{1 的}表达改变生物合成基因。然而，FvPex13 主要负责无性分生孢子繁殖和毒力，而 ΔFvpex33/14 双突变体也表现出毒力缺陷。总之，我们的研究表明 FvPex13 是 DTM 的核心成分，与其他 DTM 过氧化物直接物理相互作用，并调节过氧化物酶体膜生物发生以及 PTS1 和 PTS2 介导的跨膜货物运输。重要的是，我们还将 FvPex8 描述为影响过氧化物酶体功能和 FB ₁生物合成的轮枝杆菌DTM的关键成分。

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